True about primary lymphedema:

Ans is d i.e. Associated with Milroy's disease "The primary lymphedemas are relatively uncommon, occurring in 1 of every 10,000 individuals"-Sabiston "Lymphangiosarcoma is a rare tumor that develops as a complication of long-standing (usually more than 10 years) lymphedema."- Sabiston "Cutaneous lymphangiosarcoma may develop in chronically lymphedematous extremities."- Devita 8/e Chapter 45